A number of systems have been available for illumination. The constant which has heretofore been present in portable illumination is the design conflict between a carried or portable lighting unit and a stable or independently supported unit. As a prime example, utility lights have a large six-volt lantern size battery and are handy and balanced for carrying, but awkward for setting up for use in a free-standing application. Cylindrical in line battery type hand held flashlights have the same problem, they are difficult to temporarily set up in a free-standing position.
Further, either the lantern or single in line conventional flashlight have the limitation of a single lamp and reflector. Where a wider area is sought to be illuminated, the user has to wave the light back and forth. Where two areas of interest are fairly close together a slight waving motion is required. Where two widely separated areas of interest exist, more rapid and extreme movement is needed to keep both sides visible.
In the alternative, there are commercial light sets which range from trailer mounted light trees complete with generators. However these systems are not portable nor carryable into tight working spaces where both the ability to aim and direct the light may be compromised, as well as the ability to apply more than one source of light.
Failure mode is another area where conventional portable lighting typically fails. In a close dark work space, the failure of the main bulb element can leave a worker totally in the dark, unless he carries a backup light source. Even when a backup source is carried, it may be difficult to locate where the worker is plunged into darkness unexpectedly.